White-Beaked Dolphin

The white-beaked dolphin is a robust species of dolphin with a short beak. Adults can reach 2.3 to 3.1 m (7 ft 7 in to 10 ft 2 in) long and weigh 180 to 354 kg (397 to 780 lb). Calves are 1.1 to 1.2 m (3 ft 7 in to 3 ft 11 in) long at birth and probably weigh about 40 kg (88 lb). The upper body and flanks are dark grey with light grey patches, including a 'saddle' behind the dorsal fin, while the underside is light grey to almost white in color. The flippers, fluke, and the tall, falcate, dorsal fin are all a darker grey than the body. As the common name implies, the beak is usually white in color, but it may be a dark, ashy grey, in some older individuals.

The white-beaked dolphin is endemic to the cold temperate and subarctic waters of the North Atlantic Ocean, most commonly in seas less than 1,000 m (3,300 ft) deep. They are found in a band stretching across the ocean from Cape Cod, the mouth of the St. Lawrence River and southern Greenland in the west, around Iceland in the centre, and across in the west from northern France to Svalbard; however, they are not well adapted to truly Arctic conditions. Due to the fact they are not fully adapted to Arctic conditions, they are more vulnerable to predators, most notably polar bears. Within this wider region, white-beaked dolphins are most commonly found in four locales: on the Labrador Shelf close to southwestern Greenland, around Iceland, off the northern and eastern coasts of Britain, and off the coast of Norway.

The population, breeding pattern, and life expectancy of the dolphin are all unknown, although most sources estimate several hundred thousand individuals, more densely populated in the eastern North Atlantic than the west.

White-beaked dolphins feed predominantly on gadoid fishes, particularly cod, haddock, and whiting. They are social animals, most commonly found in groups of less than ten, but sometimes in much larger associations of over a hundred individuals. Their sonar clicks have a peak frequency of 115 kHz, while their social whistles are at around 35 kHz, and can be audible to others of their species at distances of up to 10 km (6.2 mi).

The North and Baltic Sea populations of the white-beaked dolphin are listed on Appendix II of the Convention on the Conservation of Migratory Species of Wild Animals (CMS), since they have an unfavourable conservation status or would benefit significantly from international co-operation organised by tailored agreements.

In addition, the white-beaked dolphin is covered by the Agreement on the Conservation of Small Cetaceans of the Baltic, North East Atlantic, Irish and North Seas (ASCOBANS).